Sizing agent for glass fibers

ABSTRACT

A sizing agent composition comprising a film-forming material, a lubricant for glass fibers, a coupling agent and an antistatic agent, in which the film-forming material is an oil-in-water type emulsion of an unsaturated polyester obtained by reacting under heating (a) 1 mole of a dibasic acid component containing at least 50 mole percent of fumaric acid or maleic anhydride and (b) 1 to 1.5 moles of a diol component containing at least 30 mole percent of an adduct of 2 to 10 mols of an alkylene oxide to bisphenol A, with (c) an emulsifier selected from an adduct of 5 to 200 moles of an alkylene oxide to castor oil, an adduct of 5 to 200 moles of an alkylene oxide to hydrogenated castor oil and a polyethyleneglycol having an average molecular weight of 1000 to 6000, the amount of said emulsifier (c) being 5 to 30 parts by weight per 100 parts by weight of the sum of the polyester starting materials (a) and (b), and incorporating the resulting unsaturated polyester into water, and that the antistatic agent is a compound having the formulae RSO3H.N(CH2CH2OH)3 or ROSO3H.N(CH2CH2OH)3 wherein R stands for alkyl having 8 to 20 carbon atoms or an univalent organic radical obtained from alkylbenzene, alkylnaphthalene, polyoxyethylene alkyl ether, polyoxyethylene alkylphenyl ether, naphthalene-formaldehyde condensate, dialkyl succinate or alkyldiphenyl oxide.

United States Patent Furukawa et a1.

[ Dec. 2, 1975 I SIZING AGENT FOR GLASS FIBERS [75] Inventors: Jun-ichiFurukawa; Yoshinao Kono,

both of Wakayama, Japan [73] Assignee: Kao Soap Co. Ltd., Tokyo, Japan[22] Filed: June 12, 1974 [21] Appl. No.: 478,432

[30] Foreign Application Priority Data June 27, 1973 Japan 48725l9 [52]US. CI...260/22 R; 117/126 GB; 260/292 UA; 260/296 MQ, 260/DIG. I5

[51] Int. CI. C08L 67/08; C08L 67/06 [58] Field of Search ..260/29.2 UA;29.6 MM; 260/296 MQ, DIG. 15, 16, 22 R;

117/126 GQ,126 GB Primary Examiner-Paul R. Michl Attorney, Agent, orFirmWoodhams, Blanchard and Flynn [57] ABSTRACT A sizing agentcomposition comprising a film-forming material, a lubricant for glassfibers, a coupling agent and an antistatic agent, in which thefilm-forming material is an oil-in-water type emulsion of an unsaturatedpolyester obtained by reacting under heating (a) 1 mole of a dibasicacid component containing at least 50 mole percent of fumaric acid ormaleic anhydride and (b) l to 1.5 moles ofa diol component containing atleast 30 mole percent of an adduct of 2 to 10 mols of an alkylene oxideto bisphenol A, with (c) an emulsifier selected from an adduct of 5 to200 moles of an alkylene oxide to castor oil, an adduct of 5 to 200moles of an alkylene oxide to hydrogenated castor oil and apolyethyleneglycol having an average molecular weight of 1000 to 6000,the amount of said emulsifier (c) being 5 to 30 parts by weight per 100parts by weight of the sum of the polyester starting materials (a) and(b), and incorporating the resulting unsaturated polyester into water,and that the antistatic agent is a compound having the formulaeRSO;,H.N(CH- CH OH )1; or ROSO H.N(CH- ,CH OH) wherein R stands foralkyl having 8 to 20 carbon atoms or an univalent organicradical'obtained from alkylbenzene, alkylnaphthalene, polyoxyethylenealkyl ether, polyoxyethylene alkylphenyl ether, naphthalene-formaldehydecondensate. dialkyl succinate or alkyldiphenyl oxide.

7 Claims, N0 Drawings SIZING AGENT FOR GLASS FIBERS BACKGROUND or THEINVENTION 1. Field of the invention This invention relates to a sizingagent composition for glass fibers. More particularly, the inventionrelates to a sizing agent composition for glass fibers which improvesthe surface characteristics of glass fibers and which imparts anexcellent transparency to glass fiberreinforced articles and the like.

In greater detail, the sizing agent composition, according to theinvention, is characterized by the features that a self-emulsifiableunsaturated polyester of the bisphenol type is used as a film-formingmaterial and that an anionic surface active agent such as atriethanolamine sulfate or triethanolamine sulfonate of C -C alkyl,alkylbenzene, alkylnaphthalene, polyoxyethylene alkyl ether,polyoxyethylene alkylphenyl ether, naphthalene-formaldehyde condensate,dialkyl succinate or alkyldiphenyl oxide compounds is used as theantistatic agent.

2. Description of the prior art Various surface treatments haveheretofore been applied to inorganic materials for promoting the bondingof inorganic materials and organic materials. Especially, in the art ofglass fibers, sizing agents have been playing an important role inpreparing fiber-reinforced plastics, sometimes hereafter referred to asFRI, composed of glass fibers and thermosetting resins. When glassfibers are used as a reinforcement for FRP, they are employed in theform ofa mat or in the form of separate short staple fibers. Since glassfibers tend to be statically charged, it is frequently desirable, and isindispensable in some cases, to use an antistatic agent during themanufacturing or cutting steps. If an antistatic agent is employed, itis possible to distribute the glass fibers uniformly in the laminatingor molding composition. However, if the antistatic agent is notcorrectly chosen, the fibers are caused to repel from one another bystatic charges and a non-uniform distribution of glass fibers occurs inthe composition.

Sizing of glass fibers or filaments is generally accomplished byapplying a coating composition to fiber surfaces just after extrusionand before cutting the filaments into staples. Coating compositions usedfor this purpose comprise, in general, (1 a film-forming material, (2) alubricant for glass fibers and (3) an antistatic agent. When the glassfibers are to be bonded to resins, in order to improve the bondingbetween the glass fibers and the resin, a coupling agent is usuallyincorporated into such sizing agent composition. When the glass fibersare to be used as a reinforcement for resins, the sizing agentcomposition should have a good compatibility with the resin.

Satisfactory antistatic agents should have not only a property ofpreventing generation of static charges but also a good compatibilitywith other components of the sizing agent. It is also required that theyshould not damage the desired good transparency of the final resinproducts containing the glass fibers.

Such agents as alkyl amines, quaternary ammonium salts, polyoxyethylenealkyl amines and ampholytic surface active agents of the betaine typehave generally been used as antistatic agents for glass fibers.

These prior art antistatic agents, however, have a very low effect whenapplied with self-emulsifiable polyesters of the bisphenol typeaccording to the pres- 2 ent invention. Inorganic salt antistaticagents, which have heretofore been used, such as potassium chloride,lithium chloride, ammonium chloride and the like, have a high antistaticeffect, but they are defective in that they damage greatly thetransparency of glass fiber-reinforced resin articles.

It is therefore a primary object of this invention to provide a sizingagent composition for glass fibers comprising an improved antistaticagent in combination with a self-emulsifiable polyester of the bisphenoltype.

Another object of this invention is to provide glass fibers coated withsuch improved sizing agent composition.

Still another object of this invention is to provide a sizing agentcomposition for glass fibers which can impart a better transparency toglass fiber-reinforced resin articles than conventional sizing agents.

SUMMARY OF THE INVENTION These objects of this invention can be attainedby employing a sizing agent composition for glass fibers, comprising aself-emulsifiable unsaturated polyester of the bisphenol type as thefilm-forming material, an anionic surface active agent such as atriethanolamine sulfate or triethanolamine sulfonate of C -C alkyl,alkylbenzene, alkylnaphthalene, polyoxyethylene alkyl ether,polyoxyethylene alkylphenyl ether, naphthaleneformaldehyde condensate,dialkyl succinate or alkyldiphenyl oxide compounds as an antistaticagent, in combination with known lubricant for glass fibers and a knowncoupling agent. Improved glass fibers and improved glassfiber-reinforced resin articles can be obtained by coating glass fiberswith the above-mentioned sizing agent.

The self-emulsifiable unsaturated polyester of the bisphenol typeemployed in this invention is formed by employing as a critical glycolcomponent, an alkylene oxide adduct to bisphenol A (the number of addedmoles of alkylene oxide being 2 to 10) and reacting this adduct with anunsaturated dicarboxylic acid. In preparing the above unsaturated resin,an emulsifier selected from the group consisting of polyalkyleneglycolshaving an average molecular weight of 1000 to 6000 and adducts of aplurality of moles (5 to 200 moles) of an alkylene oxide adducted tocastor oil or hydrogenated castor oil is added and allowed toparticipate in the reaction, whereby a self-emulsifiable polyester isobtained.

In order to attain one of the objects of this invention, namely theobject of obtaining glass fiber-reinforced resin articles having anexcellent transparency, it is indispensable that the above-describedunsaturated polyester resin should exhibit a substantial penetratingpower to vinyl monomers. In other words, it is indispensable that theglass fibers should be made so highly and uniformly penetrative thatwhen the glass fibers are incorporated in a resin matrix, the glassfibers should not be readily visually distinguishable from the resinmatrix and it should be difficult to observe with the naked eye that theresin matrix is reinforced by glass fibers. In the art it is well knownthat it is very difficult to obtain fiberreinforced resin articles inwhich the glass fibers are not visible or are inconspicuous. It isconsidered that the conspicuousness of glass fibers in comparison withthe resin matrix is due to the extreme coloration of the treated fibersas compared with the color of the resin matrix and to the physicalproperties (for example, refractive index and the like) of the fiberspresent on the resin surface.

Most glass fiber-reinforced resin articles are not colored with apigment. Accordingly, the undesired conspicuousness of glass fibers incomparison with the resin matrix has been a problem in the past. Anunsaturated polyester obtained by reacting an alkylene oxide adduct tobisphenol A as an indispensable diol component, with an unsaturateddicarboxylic acid optionally containing a saturated dicarboxylic acid,and a polyalkyleneglycol or alkylene oxide adduct to castor oil orhydrogenated castor oil as an emulsifier, exhibits a substantialsolubility to vinyl monomers.

The self-emulsifiable unsaturated polyester resin according to thisinvention can be obtained by mixing (a) 1 mole of a dibasic acidcomponent containing at least 50 mole percent of a material selectedfrom the group consisting of fumaric acid, maleic anhydride and mixturesthereof and (b) 1 to 1.5 moles of a diol component containing at least30 mole percent of an adduct of 2 to moles of an alkylene oxide tobisphenol A, with (c) 5 to 30 parts by weight, per 100 parts by weightof the sum of the polyester starting materials (a) and (b), of anemulsifier selected from the group consisting of an adduct of 5 to 200moles of an alkylene oxide to castor oil, an adduct of 5 to 200 moles ofan alkylene oxide to hydrogenated castor oil and a polyethyleneglycolhaving an average molecular weight in the range of 1000 to 6000, andheating the mixture to effect esterification.

The oil-in-water type emulsion of an unsaturated polyester to be used inthis invention is prepared in the following manner.

First, according to a conventional method, reactants (a), (b) and (c)are heated and reacted while removing water formed by thepolycondensation reaction. The reaction is carried out at a temperatureof 150 to 210C., preferably at 170 to 200C. The reaction is stopped whenthe acid value of the reaction mixture becomes lower than 30. Then, theresulting polyester is cooled to 100 to 105C. and is gradually added,with sufficient agitation, to water maintained at 60 to 95C., wherebythe polyester is completely emulsified and an oil-in-water emulsion ofan unsaturated polyester is obtained.

It is possible to obtain self-emulsifiable unsaturated polyesters of thebisphenol A type differing in properties, namely polyester s rangingfrom highly viscous liquids to solids having a softening point of 95C.,when the mixing ratio of (b) the alkylene oxide adduct to bisphenol A to(a) the dibasic acid, is changed optionally within the range of l to 1.5moles of (b) per one mole of (a).

It is critical that the dibasic acid component (a), used for making theunsaturated polyester, consists of 50 to 100 mole percent of fumaricacid, maleic anhydride or mixtures thereof. The balance of the dibasicacid component, that is, up to 50 mole percent thereof, can be selectedfrom other a,B-ethylenically unsaturated dibasic acids such as maleicacid and itaconic acid. It is industrially advantageous to employ adibasic acid component consisting essentially of 100 mole percent offumaric acid, maleic anhydride or mixtures thereof.

It is permissible to employ, as an optional additive, a small amount ofup to 1 moles, per 1 mole of said dibasic acid component (a), of asaturated dibasic acid such as tetrahydrophthalic anhydride, phthalicanhydride, isophthalic acid, adipic acid and succinic acid, incombination with said dibasic acid component (a).

It is critical to use as the diol component (b) of the polyesterreaction mixture, a diol component consisting of 30 to 100 molepercent-of an alkylene oxide adduct to bisphenol A. This adduct isformed by adding 2 to 10 moles of an alkylene oxide to 1 mole ofbisphenol A(2,2-bis(4-hydroxyphenylpropane)). As the alkylene oxide,there can be used, for example, ethylene oxide and propylene oxide. Thebalance of the diol component, that is, up to mole percent thereof, is(1) hydrogenated bisphenol A, (2) a diol of the following formula:

wherein n is an integer of from 1 to 4 and R is H or CH or (3) mixturesof 1 and (2). A diol of the above formula, hydrogenated bisphenol A andmixtures thereof can be used in combination with the essentialconstituent, the alkylene oxide adduct to bisphenol A. Specific examplesof diols of the above formula include ethyleneglycol, propyleneglycol,diethyleneglycol, triethyleneglyc'ol, tetraethyleneglycol,diproppyleneglycol, tripropyleneglycol and tetrapropyleneglycol.

As the emuslifier there can be used an alkylene oxide aduct to castoroil or hydrogenated castor oil, formed by adding 5 to 200 moles,preferably 50 to 150 moles, of an alkylene oxide, such as ethylene oxideor propylene oxide, to castor oil or hydrogenated castor oil. Ethyleneoxide is generally employed as the alkylene oxide. Another emulsifierthat can be used is polyethyleneglycol having an average molecularweight in the range of 1000 to 6000. Mixtures of these emulsifiers canbe used.

The unsaturated polyester, according to this invention, is prepared byreacting l to 1.5 moles of the diol component, as defined above, with 1mole of the dibasic acid component, as defined above. This reaction iscarried out in the presence of the emulsifier (c).

The amount of the emulsifier, as defined above, used for preparing anunsaturated polyester is from 5 to 30 parts by weight of emulsifier perparts by weight of the sum of the above defined dibasic acid component[the above component (a)] plus the diol component [the above component(b)]. It is possible to add minor amounts of polymerization initiator,defoaming agent and the like to the reaction mixture according to need,in a conventional manner.

The antistatic agent used in this invention is a triethanolamine sulfateor sulfonate of one or the other of the following two formulae:

Rs0 H.N CH,CH,0H) or ROSO H.N(CH,CH OH).1

As the radical R is the above formulae, there can be used (1) alkylhaving 8 to 20 carbon atoms, (2) alkylbenzene radical of the formulawherein R is alkyl having 8 to 20 carbon atoms, (3) alkylnaphthaleneradical of the formula wherein R is alkyl having 8 to 20 carbon atoms,(4) polyoxyethylene alkyl ether radical of the formula R .O(CH CHwherein R is alkyl having 8 to 20 carbon atoms and n is a number of 1 to200, (5) polyoxyethylene alkylphenyl radical of the formula wherein R isalkyl having 8 to 20 carbon atoms, (6) naphthaleneformaldehydecondensate radical of the formula (7) dialkyl succinate radical of theformula cook,

R,ooccH, cn-

wherein R is alkyl having 8 to 20 carbon atoms and (8) an alkyldiphenyloxide radical wherein R is alkyl having 8 to 20 carbon atoms.

In the sizing agent composition for glass fibers according to thisinvention, it is preferred that the antistatic agent is incorporated inan amount of 1 to parts by weight per 100 parts by weight of thefilm-forming material, calculated on a water-free basis.

Effective lubricants for use in the sizing agent composition for glassfibers according to this invention are well known and the invention doesnot relate to any discovery pertaining thereto. For example, there canbe employed oils, fats and waxes of vegetable, animal and marine animalorigin such as carnauba oil and candelilla wax, silicone oils such asdihydrocarbon polysiloxanes, glycerin, polyethyleneglycol, polyhydricalcohol esters such as esters of diethyleneglycol andtetraethyleneglycol, fatty alcohols such as lauryl alcohol and stearylalcohol, pelargone amide, and fatty acid amines such as polyvalentunsaturated fatty acid amides solubilized by an acid anhydride. 1n thesizing agent composition of this invention, it is preferred to employthe lubricant in an amount of 5 to 30 parts by weight per 100 parts byweight (water-free basis) of the unsaturated polyester of the bisphenoltype used as the film-forming material.

Effective coupling agents for use in sizing agent composition for glassfibers according to this invention also are well known and the inventiondoes not relate to any discovery pertaining thereto. As the couplingagent, there can be mentioned, for example, silanes such as vinyltriethoxysilane, vinyl triacetoxysilane, allyl trichlorosilane,aminosilane, epoxysilane and 'y-methacryloxypropyl trimethoxysilane, andsiloxanes such as vinyl trisiloxane and allyl polysiloxane. In thesizing agent composition of this invention it is preferred that thecoupling agent is incorporated in an amount of 5 to 50 parts by weightper 100 parts by weight (water-free 6 basis) of the unsaturatedpolyester of the bisphenol type to be used as the film-forming material.

The sizing agent composition according to the invention is applied tothe glass fibers in the form of an aqueous solution or emulsion thereof.Such solution or emulsion generally contains from 0.5 to 5 weight percent of the sizing agent composition, according to the invention, andthe balance is water. The sizing agent composition is applied in aconventional manner such as by spraying it onto the glass fibers orimmersing the glass fibers therein. The coated glass fibers are thendried, for example, in an oven or in ambient air, to remove the waterwhereby the glass fibers are uniformly coated by the coating agentcomposition. It is effective to apply the sizing agent composition sothat the glass fibers are coated with from 0.5 to 2 weight percent ofthe sizing agent composition, calculated on a waterfree basis, based onthe weight of the glass fibers.

This invention will now be further described by reference to thefollowing illustrative Examples.

EXAMPLE 1 A reaction vessel equipped with an agitator, a thermometer, anitrogen gas introduction tube and a waterremoving tube was charged with1050 (3.0 moles) of 2.0 prodendro-bisphenol A (adduct of 2.0 moles ofpropylene oxide to bisphenol A), 323 g (2.8 moles) of fumaric acid, 343g of polyethyleneglycol No. 1500 (having an average molecular weight ofabout 1500), 1.0 g of hydroquinone and 0.3 g of silicone (marketed underthe tradename Toshiba Silicone TSA-730) as a defoaming agent, and themixture was heated and reacted at 160 to 210C. in a nitrogen gascurrent. The reaction was stopped when the acid value of the formedpolyester was 25. The reaction product was cooled to 100C and then wasgradually poured with agitation into water maintained at to C. to obtaina homogeneous unsaturated polyester emulsion. The water content of thethus-obtained oil-in-water type unsaturated polyester emulsion was soadjusted that the polyester concentration was 30 percent by weight.

Using the above ernulsion, a sizing composition of the following recipewas prepared by mixing:

The pH of the above sizing composition was 7.1. Emanone 31 10, which ispolyethyleneglycol monostearate, was added as an emulsion stabilizer forthe above sizing composition.

A satin weave glass cloth was dipped in this emulsion, and then thecloth was air-dried and heated at C. for 1 hour to age the sizing agent.Prior to this sizing treatment, the cloth was sufficiently washed andcut into a size of 20 cm X 20 cm. The thus-coated square glass cloth wasallowed to stand still overnight under the conditions of a temperatureof 25C. and a relative humidity of 60 percent. Then, the surfaceresistivity of the cloth was measured by a high resistance meter man- '7ufactured by Yokokawa Denki. The amount of the sizing compositionapplied to the glass cloth was 0.74 percent.

Using the thus-obtained coated cloth, a -layer laminate of a glasscloth-reinforced polyester resin (the glass content being 25 to 30 wt.percent) was prepared. The resin used was Epolac N-35OL (isophthalatetype) manufactured by Nippon Shokubai. Cobalt naphthenate andmethylethylketone peroxide were used as a curing promotor and a curingcatalyst, respectively, and the room temperature curing time wasadjusted to from 20 to 30 minutes.

The laminate was subjected to a post-curing treatment for 1 hour at 110to 120C., and after the laminate was cooled, samples having a size of 5cm X 5 cm were cut from the laminate. Using such test samples, the lighttransmission was measured by means of a haze meter manufactured by ToyoRikakogyo, and the transparency was evaluated.

For comparison, in the same manner as described above, a sizingcomposition was prepared by employing a vinyl acetate copolymer, whichis conventionally employed as a film-forming material for glass fibers,and

Surface Resistivity Transparency product of this 4.2 X Dem 140 inventioncomparative 4.8 X 10'' Dem 100 product Note The transparency isexpressed in terms oi the light transmission measured according to theabove method and is a relative value based on the light transmission(assigned the arbitrary value of 100) of the comparative product.

From the above results, it will readily be understood that the sizingagent composition of this invention has a sufficiently high antistaticeffect and gives a laminate having a much higher transparency than thatof a laminate treated with the conventional sizing agent composition(comparative product).

EXAMPLE 2 The same reaction vessel as used in Example 1 was charged with1037 g (3.2 moles) of an adduct of 2 moles of ethylene oxide tobisphenol A, 294 g (3.0 moles) of maleic anhydride, 330 g of an adductof 100 moles of ethylene oxide to castor oil, 1.0 g of hydroquinone and0.3 g of silicone (marketed under the tradename Toshiba SiliconeTSA-730) as a defoaming agent. and the mixture was heated and reacted atl60to 210C. in a nitrogen gas current. A reaction product having an acidvalue of 25 was obtained by conducting the reaction for about 6 hours.Then, the product was cooled to 100C. and was gradually poured underagitation into water maintained at 70to 80C. to obtain a homogeneousemulsion. The thusobtained oil-in-water type unsaturated polyesteremulsion was so adjusted that the polyester concentration was 30 percentby weight.

8 Using the thus-obtained emulsion, a sizing agent composition of thefollowing recipe was prepared by mixing:

The pH of the above sizing composition was 6.9.

In the same manner as in Example 1, a glass cloth was treated with thethus-formed sizing agent composition and dried. The surface resistivityof the treated glass cloth and the transparency of a laminate preparedin the same manner as in Example 1 from this glass sheet weredetermined. The amount of the sizing composition applied to the glasscloth was 0.81 percent.

Results of the measurements are as follows:

Surface Resistivity Transparency 5.5 X 10* Gem l44 (same basis as inExample 1) From the results shown above, it will readily be understoodthat as compared with the comparative product used in Example 1, thesizing agent of this invention has a sufficiently high antistatic effectand gives a laminate excellent in transparency.

EXAMPLE 3 The same reaction vessel as used in Example 1 was charged with566.9 g (1.6 moles) of an adduct of 2 moles of propylene oxide tobisphenol A, 580 g (2.8 moles) of hydrogenated bisphenol, 488 g (4.2moles) of fumaric acid, 340 g of polyethyleneglycol having an averagemolecular weight of 4000, 1.5 g of hydroquinone and 0.5 g of silicone(marketed under the tradename Toshiba Silicone TSA-730), and the mixturewas heated and reacted at 160 to 210C. in a nitrogen current. A reactionproduct having an acid value of 29 and a softening point of C. wasobtained by conducting the reaction for about 10 hours. The reactionproduct was cooled to 140C. and was gradually poured with agitation inhot water maintained at 90 to C. to obtain a homogeneous unsaturatedpolyester emulsion. The thus-obtained oil-in-water type unsaturatedpolyester emulsion was adjusted so that the polyester concentration was30 percent by weight.

Using the thus-prepared emulsion, a sizing agent composition composed ofthe following materials was prepared by mixing:

The pH of the above sizing composition was 6.5.

A glass sheet was treated with the above sizing composition and dried inthe same manner as described in Example 1. The surface resistivity ofthe treated glass cloth and the transparency of a laminate prepared fromthe treated glass sheet were measured in the same manner as described inExample 1 to obtain the following results:

Surface Resistivity Transparency 6.0 X Qcm 145 (same basis as Example 1)The amount of the sizing composition applied to the glass cloth was 0.81percent.

From the above results, it will readily be understood that, as comparedwith the comparative product used in Example 1, the sizing agent of thisinvention has a sufficiently high antistatic effect and gives a laminateof high excellent transparency.

EXAMPLE 4 The same reaction vessel as used in Example 1 was charged with1128 g (3.2 moles) of an adduct of 2 moles of propyleneglycol, 314 g(3.2 moles) of maleic anhydride, 120 g (0.8 mole) of phthalic anhydride,430 g of an adduct of 100 moles of ethylene oxide to hydrogenated castoroil, 1.5 g of hydroquinone and 0.7 g of silicone (marketed under thetradename Toshiba Silicone TSA-730), and the mixture was heated andreacted at 160 to 210C. in a nitrogen current. A reaction product havingan acid value of 24 was obtained by conducting the reaction for about 11 hours. The reaction product was cooled to 100C. and was graduallypoured with agitation into water maintained at 70 to 80C. to obtain ahomogeneous unsaturated polyester emulsion. The resulting oil-in-watertype unsaturated polyester emulsion was adjusted so that the polyesterconcentration was 30 percent by weight.

Using the thus-obtained emulsion, a sizing agent composition composed ofthe following materials was prepared by mixing:

The pH of the above sizing composition was 6.8

A glass cloth was treated with the above sizing agent composition anddried in the same manner as described in Example 1. The surfaceresistivity of the treated cloth and the transparency of a laminateprepared from the treated glass cloth were determined in the same manneras described in Example 1 to obtain the following results:

Surface Resistivity 3.0 X 10" Gem Transparency 133 (same basis asExample 1) The amount of the sizing composition applied to the glasscloth was 0.85 percent.

From the results shown above, it will readily be understood that ascompared with the comparative product used in Example 1, the sizingagent of this invention has a sufficiently high antistatic effect andgives a laminate of high excellent transparency.

The embodiments of the invention in which an exclusive property orprivilege is claimed are defined as follows:

1. In a sizing agent composition for glass fibers comprising afilm-forming material, a lubricant for glass fibers, a coupling agentfor glass fibers and an antistatic agent, the improvement whichcomprises employing as the film-forming material an oil-in-water typeemulsion of an unsaturated polyester obtained by the reaction of (a) 1mole of a dibasic acid composition containing at least 50 mole percentof a material selected from the group consisting of fumaric acid, maleicanhydride and mixtures thereof, (b) l to 1.5 moles of a die] componentcontaining at least 30 mole percent of an adduct of 2 to 10 moles of analkylene oxide to bisphenol A with (c) an emulsifier selected from thegroup consisting of an adduct of 5 to 200 moles of an alkylene oxide tocastor oil, an adduct of 5 to 200 moles of an alkylene oxide tohydrogenated castor oil and polyethyleneglycol having an averagemolecular weight of 1000 to 6000, the amount of said emulsifier (0)being 5 to 30 parts by weight per parts by weight of the sum of thepolyester starting materials (a) and (b), and incorporating theresulting unsaturated polyester into water, and employing an antistaticagent of one of the following formulae wherein R is selected from thegroup consisting of (1) alkyl having 8 to 20 carbon atoms, (2) alkylbenzene radical of the formula wherein R is alkyl having 8 to 20 carbonatoms, (3) alkylnaphthalene radical of the formula wherein R is alkylhaving 1 to 20 carbon atoms, (4) polyoxyethylene alkyl ether radical ofthe formula a- 2 2),..

wherein R is alkyl having 8 20 carbon atoms and n is a number from 1 to200, (5) polyoxyethylene alkyl phenyl radical of the formula 1 1 12wherein R is alkyl having 8 to 20 carbon atoms, (6) from the groupconsisting of hydrogenated bisphenaphthalene-formaldehyde condensateradical of the no] A, diol of the formula formula HO+CHCH O+,, H CH 5 l2 R wherein n is an integer from 1 to 4 and R is H or (7)dialkylsuccinate radical of the formula CH3, and mixtures th f component(c) is selected from the group consisting 5 iC of an adduct of 5 to 200moles of an alkylene oxide COORS to castor oil, an adduct of 5 to 200moles of an alkylene oxide to hydrogenated castor oil and polyethyleneglycol having an average molecular weight of 1000 to 6000, and component(d) is up to 1 moles, per one mole of said component (a)( l) i of amaterial selected from the group consisting of R tetrahydrophthalicanhydride, phthalic anhydride,

6 20 isophthalic acid, adipic acid, succinic acid and mixtures thereofthe reaction being carried out until the acid value of the wherein R isalkyl having 8 to 20 carbon atoms, and (8) alkyldiphenyl oxide radicalof the formula wherein R is alkyl having 8 to carbon atoms, the Qcomposition containing from 1 to 15 parts by weight of reaction mixtureis less than 3:) and then adding the resaid antistatic agent per 100parts by weight of said actlon mlxture to at 60 F 95 emulsion,calculated as the Solids 3. A method according to claim 2 wherein saidalkyl- 2. A composition according to claim 1, in which said ene Oxide isethylene QXide or Propylene i emulsion is obtained by reacting at atemperature of A method accordmg to clalm wherem compo 150 to 210C, areaction mixure consisting of compo- (3) consists of fumarlc acidnents(a), (b), (c) and (d) wherein the mole ratio of A method according toClaim 3, wherein p (b)/(a) is 1.0 to 1.5 /1.0 and the weight ratio ofHem Consists of maleic anhydridel (b) i (5 to 30)/1()() 6. A coatedproduct comprising glass fibers or mats h i of glass fibers coated withfrom 0.5 to 5 weight percent component (a) consists of (l) 50 to 100mole perof a composition according to claim 1, based on the cent of amaterial selected from the group consiswflight 0f the glass fibersing offumaric a id, l i h drid d i t 7. A method of sizing glass fibers ormats of glass fithereof, and (2) the balance of (a) is afi-ethylemiberswhich comprises applying an aqueous solution or cally unsaturateddibasic acid, emulsion of the composition defined in claim 1 to thecomponent (b) consists of (1) 30 to 100 mole perglass fibers and thenevaporating water from the comcent of an adduct of2 to 10 moles ofalkylene oxide position to deposit a coating on said glass fibers. tobisphenol A, and (2) the balance is selected 40 UNITED STATES PATENTOFFICE CERTIFICATE OF CORRECTION Patent 3 923 708 Dated December 2, 1975Inventoflg) Jun-ichi Furukawa and Yoshinao Kono It is certified thaterror appears in the above-identified patent and that said LettersPatent are hereby corrected as shown below:

Col. 10, line 18; change "composition" to component.

Col. 10, line 61; change "8 '20" to 8 to 20.

Signed and Scaled this thirtieth D f March 1976 [SEAL] Attest:

RUTH C. MASON C. MARSHALL DANN Arresting Officer Commissioner nj'Palentsand Trademarks UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTIONPatmm NO- 3 923 708 Datmi December 2, 1975 1nvauwr(s) Jun-ichi Furukawaand Yoshinao Kono It is certified that error appears in theabove-identified patent and that said Letters Patent are herebycorrected as shown below:

Col. 10, line 18; change "composition" to -component.

Col. 10, line 61} change "8'20" to -8 to 20-.

Signed and Sealed this thirtieth D 3y of March I 9 76 [SEAL] A ttest:

RUTH C. MASON C. MARSHALL DANN Arresting Officer Commissioner oj'Patentsand Trqdemarkx

1. IN A SIZING AGENT COMPOSITION FOR GLASS FIBERS COMPRISING AFILM-FORMING MATERIAL, A LUBRICANT FOR GLASS FIBERS, A COUPLING AGENTFOR GLASS FIBERS AND AN ANTISTATIC AGENT, THE IMPROVEMENT WHICHCOMPRISES EMPOLYING AS THE FILM-FORMING MATERIAL IN OIL-IN-WATER TYPEEMULSION OF AN UNSATURATED POLYESTER OBTAINED BY THE REACTION OF (A) 1MOLE OF A DIBASIC ACID COMPOSITION CONTAINING AT LEAST 50 MOLE PERCENTOF A MATERIAL SELECTED FROM THE GROUP CONSISTING OF FUMARIC ACID, MALEICANHYDRIDE AND MIXTURES THEREOF, (B) 1 TO 1.5 MOLES OF A DIOL COMPONENTCONTANING AT LEAST 30 MOLE PERCENT OF AN ADDUT OF 2 TO 10 MOLES OF ANALKYLENE OXIDE TO BISPHENOL A WITH (C) AN EMULSIFIER SELECTED FROM THEGROUP CONSISTING OF AN ADDUCT OF 5 TO 200 MOLES OF AN ALKYLENE OXIDE TOCASTOR OIL, AN ADDUCT OF 5 TO 200 MOLES OF AN ALKYLENE OXIDE TOHYDROGENATED CASTOR OIL AND POLYETHYLENEGLYCOL HAVING AN AVERAGEMOLECULAR WEIGHT OF 1000 TO 6000, THE AMOUNT OF SAID EMULSIFIER (C)BEING 5 TO 30 PARTS BY WEIGHT PER 100 PARTS BY WEIGHT OF THE SUM OF THEPOLYESTER STARTING MATERIALS (A) AND (B), AND INCORPORATING THERESULTING UNSATURATED POLYESTER INTO WATER, AND EMPLOYING AN ANTISTATICAGENT OF ONE OF THE FOLLOWING FORMULAE
 2. A composition according toclaim 1, in which said emulsion is obtained by reacting at a temperatureof 150* to 210*C, a reaction mixure consisting of components (a), (b),(c) and (d) wherein the mole ratio of (b)/(a) is (1.0 to 1.5)/1.0 andthe weight ratio of (c)/(a) plus (b) is (5 to 30)/100, wherein component(a) consists of (1) 50 to 100 mole percent of a material selected fromthe group consising of fumaric acid, maleic anhydride and mixturesthereof, and (2) the balance of (a) is Alpha , Beta -ethylenicallyunsaturated dibasic acid, component (b) consists of (1) 30 to 100 molepercent of an adduct of 2 to 10 moles of alkylene oxide to bisphenol A,and (2) the balance is selected from the group consisting ofhydrogenated bisphenol A, diol of the formula
 3. A method according toclaim 2 wherein said alkylene oxide is ethylene oxide or propyleneoxide.
 4. A method according to claim 3, wherein component (a) consistsof fumaric acid.
 5. A method according to claim 3, wherein component (a)consists of maleic anhydride.
 6. A coated product comprising glassfibers or mats of glass fibers coated with from 0.5 to 5 weight percentof a composition according to claim 1, based on the weight of the glassfibers.
 7. A method of sizing glass fibers or mats of glass fibers whichcomprises applying an aqueous solution or emulsion of the compositiondefined in claim 1 to the glass fibers and then evaporating water fromthe composition to deposit a coating on said glass fibers.